The present invention relates to a method for handling powderous materials comprising fine particulate. More particularly, the invention pertains a method for distributing a zeolite, such as a molecular sieve powder.
Zeolites, such as molecular sieves, have a crystalline structure that is particularly suited for adsorbing odorous materials. Zeolites are both naturally occurring and synthetically produced. Zeolites are inherently statically charged insulators that electrostatically attract the adsorbates. In addition to driving the absorptive forces, however, the static charge of zeolites, more specifically molecular sieves also lead to material handling difficulties. In the past, these difficulties have rendered the use of zeolites, including molecular sieves, uneconomical and/or problematic for many applications.
Static electricity causes zeolite powder to agglomerate during processing into relatively large, non-uniform clusters having substantial integrity. These clusters reduce the cost effectiveness of the final product and the performance efficiency of the zeolite by causing a very high degree of powder weight add-on variability and non-uniform deposition. Additionally, an unacceptably large amount of the statically charged particles tend to become airborne and contaminate the working environment. Due to their electrical charge, the zeolite particles cannot thereafter be easily removed from working surfaces by airjets or vacuum.
Previous attempts to manage the foregoing processing problems associated with zeolites have focused on increasing the particle size, either by increasing the size of the zeolite itself or by bonding the zeolite, such as a molecular sieve, to another substance. While increasing the particle size may lessen somewhat weight add-on variability and reduce deposition non-uniformity, this approach remains unsatisfactory. The larger zeolites or zeolite composites are cost prohibitive for many applications and do not significantly reduce airborne dust contamination.
Therefore, what is lacking and needed in the art is an economical approach to distributing zeolite, and more specifically molecular sieve, powders.